SCHAEFERSeries 303 Aluminum Blocks

Use as sheet control blocks on dinghies, or for control lines on larger boats. High-impact Delrin® sheaves turn on polished stainless steel spacers, so the cheeks won't squeeze or bind the sheave, even under extremely heavy loads. Head shackles are stamped stainless steel with clevis pin and cotter ring. Cheeks are black hard-coated anodized aluminum. Straps, headclips, shackles, and rivets are tumbled and polished stainless steel.

Use as sheet control blocks on dinghies, or for control lines on larger boats. High-impact Delrin® sheaves turn on polished stainless steel spacers, so the cheeks won't squeeze or bind the sheave, even under extremely heavy loads. Head shackles are stamped stainless steel with clevis pin and cotter ring. Cheeks are black hard-coated anodized aluminum. Straps, headclips, shackles, and rivets are tumbled and polished stainless steel.

Sheave: Delrin

Sheave Size: 1-7/16"

Line Diameter: 7/16"

Cheek Material/Finish: Aluminum

Safe Working Load: 1,000lb.

Specs

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Side Shackle

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Single

Weight

2.6 Ounces

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Swivel Shackle

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Single

Weight

2.7 Ounces

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Mechanical Fasteners

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Single Cheek/Foot

Weight

2.5 Ounces

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Side Shackle

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Double

Weight

4.1 Ounces

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Mechanical Fasteners

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Double Cheek/Foot

Weight

4.2 Ounces

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Mechanical Fasteners

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Single Cheek/Foot

Weight

2.2 Ounces

Becket

No Becket

Diameter

7/16 Inch or 11 mm

Direction

Any

Integral Cleat

No Integral Cleat

Mount Type

Mechanical Fasteners

Ratchet

Non Ratcheting

Safe Working Load

1000 Pounds

Sheave Diameter

37 mm

Type

Single Upright

Weight

3 Ounces

West Advisor

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I have Schaefer blocks all over my boat. Some are more than 10 years old. Maintenance has just been hosing them off or letting the rain do it. None have ever failed or exhibited excess friction. The price is right and the look fine.